Magnetic disk drives which write and read digital data from flexible magnetic disks have been extensively used. "Floppy disk drives" have been extensively used for small, so-called microcomputer systems, for word-processing applications and the like. The flexible disk cartridge includes a relatively thin, flexible jacket which is inserted into the floppy disk drive.
Rigid disk drives, such as the IBM 3350, usually have a fixed rigid magnetic media. The magnetic heads do not contact the magnetic surface, but ride on a thin film of air. Because of this, and other features, these disk drives are capable of extremely precise and high speed operation. This type of disk drive is commonly referred to as a "Winchester" drive. Rigid disks enclosed in a rigid, removable cartridge, or shell have also been used. U.S. Pat. No. 4,864,452--Thompson et al is an example of such a drive. "Bernoulli" disk drives having performance characteristics similar to that of Winchester drives, but with removable cartridges, have been developed. A flexible magnetic disk is enclosed in a rigid box which is normally completely closed. U.S. Pat. No. 4,400,748--Bauck, et al and related patents to the common assignee show such drives using Bernoulli stabilized flexible disks. U.S. Pat. No. 4,901,173--Jones et al and related patents to the common assignee, show improvements which relate to so-called "half height" drives.
The cartridges for these drives have a door which closes the cartridge when it is removed from the drive. This prevents debris from contaminating the magnetic recording medium when the cartridge is not in the drive. When the cartridge is inserted into the drive, this door slides to an open position to provide access for the magnetic recording heads to engage the recording medium.
When the cartridge is removed from the drive, it is often subject to rough handling. During handling, physical contact of the disk with the shell may damage the disk, particularly if the disk and cartridge shell are subject to excessive "rattling".
U.S. Pat. No. 5,444,586, Iftikar, et al. discloses a mechanism for clamping the cartridge against the cartridge shell when the cartridge is removed from the drive and releasing the clamping mechanism when the cartridge is inserted into the drive. In the Iftikar, et al patent a nut and screw mechanism is actuated by a tang which is rotated as the cartridge is inserted into the drive. Unfortunately, such a design requires added complexity of the drive because the mechanism to actuate the tang is disposed within the drive, as distinguished from within the cartridge.
U.S. Pat. No. 5,650,899 Schick, et al. discloses a cam mechanism which clamps the hub against the cartridge shell as the access door of the cartridge is opened and closed when the cartridge is inserted into or ejected from the drive.
It is a goal of the present invention to provide an advantageous clamping mechanism which is actuated by the opening and closing of the cartridge door as it is inserted into and ejected from the drive, which optimizes head space, which reduces the number of moving parts, and which diminishes rattling of the cartridge while the cartridge is outside of the drive.